You know it's highly improbable, but you just can't help going mushy over the sweetest love stories ever animated. (And hey, it's entertaining!)

Kanon (2006)
QUOTE(Anime News Network)
Yuichi Aizawa returns to this city after seven years. In his childhood, he often visited it, but something happend in the past which caused him to block out his memories of the events of seven years ago. On the day after he gets settled in, he meets a girl carrying a backpack with wings on it. Her name is Tsukimiya Ayu and he begins to recall the memories he had lost.

Ouran Koukou Host Club
Haruhi is a poor tomboyish student at a school for the ultra-wealthy, able to attend because of a scholarship, and unable to even afford a uniform. One day, she stumbles across the decidedly peculiar but very popular Ouran Host Club. She tries to leave, but accidentally breaks a vase, and unable to pay for it, she's told that she'll have to stay and do odd jobs. That is, until they decide she would be more valuable as a club member. Not realizing she's female due to her appearance, they fix her up and give her a male uniform. She's an instant hit, so they decide to have her keep up the charade even after they find out the truth. Haruhi, being average almost to a fault, doesn't know what to make of the unconventional activities of the Host Club (or of the even more unconventional members), but having little choice, she plays along. Before long, real bonds are formed, friends made, and Haruhi finds herself accepted in a way she could never have been otherwise in this affluent school.

Yamato Nadeshiko Shichi Henge (aka Perfect Girl Evolution, The Wallflower)
Kyouhei, Ranmaru, Takenaga, and Yukinojou are beautiful, handsome, young men living in a huge mansion. One day, their landlord, whom they call "Auntie", asks them a favor: to make her niece, Sunako, who's going to be living with them, into a respectable young lady. She agrees to make their living expenses free of charge if they succeed but, if they fail, she'll triple their rent. Due to their confidence in knowing how to deal with women, they agree but, once they meet Sunako, they begin to realize that their lovely living arrangements may soon be in jeopardy.